Technical Notes

TECHNICAL NOTES ON ENCAPSULATED TRANSFORMERS

SAFETY ISOLATING TRANSFORMERS

It is a type of transformer which guarantees the isolation between circuits for very low voltage, becoming indicated for class II applications. Under any circumstances, 50V mustn't be exceed in secondary windings.

It is shown in the body of the transformer with the following shapes.

MARKING

PRIMARY/SECONDARY VOLTAGE

Primary Voltage, this is the supply voltage assigned to the transformer by manufacturer, to achieve the secondary power indicated for the working secondaries conditions. Secondary Voltage, is the voltage supplied by the transformer at secondary circuit with pri mary voltage at nominal value and secondary indicated current.

AMBIENT TEMPERATURE / THERMAL CLASS

Ambient temperature, the maximum temperature that transformer can be operate in a continuous mode under nominal conditions. Thermal class, it indicates the highest temperature that any material in the transformer can reach when working, it is shown with a letter after that ambient temperature accord ing the IEC60216 standard.

                     (E-120ºC) (B-130ºC) (F-155ºC) (H-180ºC)

SECONDARY POWER

Secondary power, indicated in the catalogue supplied by the secondary of transformer, when the primary gets the nominal conditions. For example 1,5VA at ta40ºC/B. for dual sec ondaries the total power corresponds to the sum of two windings. If the secondary is in tended to be connected to a rectifier bridge and smooth capacitors, to supply DC voltage, the power required is quite more bigger than V*I sec. product, to help you to determine the right transformer power our technical dept. will help you.